Perfusion sera, used in the medical field, are often packaged in a sterile manner in containers. These containers can be glass bottles, semirigid bottles of a synthetic material, or flexible bags.
Extraction of the liquid contained in the container and possible additions of medicines are performed in different ways depending on the type of container in question.
For bottles of glass or semirigid material, access to the liquid is achieved by piercing a molded rubber stopper sealing these containers. Generally the stopper is covered with a metal cap whose central part can be removed. Since this cap does not cover the stopper in a fluid tight manner, it is necessary to asepticize the stopper surface before piercing it with a syringe needle containing an additive or with a trocar connected to a perfusion tube, or again before the first of these two operations when they are performed successively with a short time gap.
The drawback of this solution is that it is costly, because of the structure of the elements used, and that it requires an asepticizing operation calling for care and attention, causing a loss of time and requiring a suitable sanitizing means.
Flexible bags are generally equipped with a tube at whose end the stoppering and connecting take place.
There are now two main solutions for stoppering and connecting flexible bags.
According to the first solution, the perfusion tube exhibits a conically shaped end, called Luer conicity, fitting over a female cone of the tip stoppering the bag. After connection, flow of the liquid is achieved by breaking this stopper.
The main drawback of this system lies in the non-interchangeability of the bag with a bottle, because extraction of the liquid from a bottle requires, as indicated above, the use of a perfusion tube ending in a trocar. But in the case of the flexible bag, the perfusion tube in place ends in a Luer conical tip. However, it would be advantageous to be able to perform, after perfusion with a solution in the bag, other perfusions with products contained in bottles, because a certain number of products cannot be stored in a polyvinyl chloride bag. This cannot easily be done because the tips of the bags and bottles are not compatible.
Further, when a perfusion has been installed on a patient, the medical personnel want to keep the tube and needle mounted in the vein as long as possible, for the obvious comfort of the patient. This is why bags equipped with a Luer conical tip are hardly ever used in perfusion.
Moreover, this arrangement, for the same reasons, has the drawback of not facilitating the introduction of additional products.
Another solution consists in equipping the end of the tube, connected to the bag, with a stopper-holding tip which is a piece having the same inside dimensions as the mouth of a small bottle, and with a stopper and cap identical with those described above in the case of rigid or semirigid containers. Use of this tip therefore comes exactly to the deficiencies of the use of a bottle as indicated above.